Bitumen Binders Modified with Sulfur/Organic Copolymers

Production of Distilled Bitumen from High-Viscosity Crude Oils of Ukrainian Fields

The characteristics of initial crudes of Yablunivske field (Poltava, Ukraine) and the properties of blended crudes have been examined to select the ways of their further processing. The crude oils were found to be heavy high-sulfuric oils without light distillates. The possibility of obtaining paving bitumen from blended crudes under study has been considered. Distilled bitumen obtained through distillation of this blend was found to meet the requirements for commercial paving bitumen 100/150. To improve the durability and resistance to aging of resulting bitumen, a polymeric modifier was added. The modifier amount of 3 wt.% was found to be appropriate to improve the operational characteristics of obtained bitumen to those of BMW 60/90 grade.

Obtaining of Formaldehyde Modified Tars and Road Materials on Their Basis

The process of chemical modification of tar and oxidized bitumen with formalin (a 37% aqueous solution of formaldehyde) in a hermetic container was investigated and the effectiveness of the proposed process was proven. It is shown that the most effective raw material for the process is tar, not oxidized bitumen. The expediency and impact of using different types of solvents (toluene, p-xylene and petroleum solvent, and n-octane) in the modification process were studied. It was established that the solvent should be used in the modification of oxidized bitumens, not tars. The low efficiency of the process of tar modification with formaldehyde without the use of a catalyst was proven, and it was shown that the most active catalyst in the process is sulfuric acid. The influence and optimal values of the main factors controlling the process of chemical modification of tar with formaldehyde were established, namely temperature, duration, and content of the modifier-formaldehyde. On the basis of the found regularities and optimal conditions of the modification process, samples of binding materials (of different brands) with different operational characteristics were obtained, and their comprehensive research was carried out. With the help of FTIR spectroscopy, the chemical interaction of tar with formaldehyde in the presence of an acid catalyst was confirmed. The design of the compositions of asphalt concrete mixtures using formaldehyde-modified tar was carried out, from which cylindrical samples of stone mastic asphalt (SMA-15 brand) were obtained, which were tested according to the main indicators: average density, water-saturation, compression strength at 20 and 50 °C, compression strength after water-saturation (MPa) at 50 °C.

Production of Bitumen Modified with Low-Molecular Organic Compounds from Petroleum Residues. 5. Use of Maleic Anhydride for Foaming Bitumens

The possibility of using maleic anhydride as a foaming agent to produce foamed bitumen was investigated. The optimal content of maleic anhydride was determined according to the indicators of the growth of the binder volume and the half-life of the foam. With use of maleic anhydride as a foaming agent, foamed bitumen was obtained, and later was used to obtain two samples of stone mastic asphalt, which differed in mixing and compaction temperatures of stone mastic asphalt mix. For comparison, the composition of stone mastic asphalt mix was designed using non-foamed (BND 70/100 and BND 70/100 modified with maleic anhydride) and foamed bitumen (BND 70/100 foamed with maleic anhydride at two different temperatures). Stone mastic asphalt specimens were formed and tested